A few mouths ago my oil pump went out. So I replaced it and the car ran fine and had no vale train noise. The oil pressure was good and strong. A week ago I was going to work and as I got on the highway I hit fifth gear, I herd the valve train, I got to work and opened the hood and plain as day I could her the lifters. What would make this happen, the motor only has 20,000 on it so it is not that old, and also the motor stated buring oil right after I need some help.
__________________
79 Mercury Capri- 89 GT ground effects.
306, Hooker long tube headers, E-303 cam, Carter AFB 650 cfm carburetor sitting on a 65 GT500 intake manifold, A/C delete. 5-speed.
To come--4.10 gears, subframe connectors, 5 lug kit, Magnaflow(headers back)
your not hearing the lifter itself. its either a bent pushrod, a collapsed lifter, or a loose rocker arm. pull your valve covers and check your rocker arms. if they are pedestal mount they should all be tight. if they are stud mount you will need an instruction manual to check the backlash. if your burning oil it sounds like you might have a ring prob. or you have a bad valve seal. do you have blue smoke coming out of your exhaust?
__________________
84 gt, 351w, rpm airgap intake, 292h comp cam, comp 1.6 roller rockers, holley 750 double pumper, roush 200 windsor sr. heads, msd ignition, 9mm ford racing wires, bbk shortys, flowmaster header back exhaust, b&m short throw shifter, centerforce dual friction clutch, billet clutch quad., 3.73 rear, 5 lug conversion w/ 17x8's front & 17x9 bullit wheels rear, saleen spoiler, custom hood, custom sub frames, ALL work done personally
I had to replace my fulcrums at only 57,000 miles, they were very noisy. I don't know if that helps, since you experienced such a dramatic change almost overnight.
I checked the rocker arms the other day and they were all torqed to specifications. The push rods were new when I rebuilt the motor, I have some smoke that comes out of my pipes but it is more grayish black but I can smell oil when I get on the gas a little. The oil was a half a quart low, I guess that would be the buring oil.
__________________
79 Mercury Capri- 89 GT ground effects.
306, Hooker long tube headers, E-303 cam, Carter AFB 650 cfm carburetor sitting on a 65 GT500 intake manifold, A/C delete. 5-speed.
To come--4.10 gears, subframe connectors, 5 lug kit, Magnaflow(headers back)
What will cause lifter noise 
